Page 100 - PortGPT_V2.1_C8_Flipbook
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Here,
                  •  initialisation_expression: In this expression, a variable is initialized which is also known as loop
                      control variable. This expression is executed only once in a loop.

                  •  conditional_expression: This expression contains a logical condition which returns either True
                      of False. If the condition evaluates to True, the statements written inside the loop body will
                      execute. If the condition evaluates to False, the statements written inside the loop body will be
                      skipped. Loop will terminate once the condition becomes False.
                  •  update_expression: This expression is executed after every pass of the loop. A pass of a loop is
                      known as an iteration. In this expression, the loop control variable is updated by increasing or
                      decreasing its value.

                  •  Loop body: This section contains the statements that are to be executed repeatedly enclosed
                      whin the curly braces.
                  Ensure that every expression should be terminated with a semicolon in the for loop, otherwise an
                  error will occur.

                  For example,

                  for(i=0; i<5; i++)
                  {
                      document.write(i);

                  }
                  In the preceding code, you can see that the variable i is initialised with the value 0. Next, a logical
                  condition i<5 is evaluated and returns True as the value of i is less than 5. After this, the variable i
                  is increased by 1 with the help of increment operator. In the body of the for loop the value of i is
                  printed. When the loop is executed once, the value of the variable i becomes 1 which is still less than
                  5. So, the loop will execute again and again until the value of the variable i becomes 5 and displays
                  the value of variable i every time.  Let us use the for loop in a web page.


                   Program 1: To create a web page that displays the table of 2 using for loop in JavaScript.

                  <HTML>

                  <HEAD>
                  <TITLE> Using for Loop </TITLE>
                  </HEAD>
                  <BODY>

                  <H2> Using for Loop to Display the Table of 2 </H2>
                  <SCRIPT>
                  var n=2;
                  for(var i = 1; i <= 10; i++) {

                      var result = n * i;
                      document.write(n + " x " + i + " = " + result+"<BR>");
                  }


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